ANDY MURRAY admitted to an uncomfortable opening to his Wimbledon campaign after being made to sweat by a tricky opponent in Mikhail Kukushkin amid on-court temperatures on Centre Court which reached 41 degrees Celsius.

The world No.3 prevailed by a 6-4, 7-6 (7-3), 6-4 scoreline against the world No.58 from Kazakhstan, but admitted he was frustrated about parts of his performance.

The Scot had his serve broken three times in the course of the second set alone but still managed to get the job done in straight sets in two hours 12 minutes.

It continued his record of never losing an opening round match at Wimbledon.

“I haven't played loads of matches on that court when it has been as warm as that,” said the Scot, who now faces Robin Haase of the Netherlands in the next round.

“You know, the day I played Novak in the final, it was extremely hot, but I don't remember playing so many matches at Wimbledon where it was into the 30s.

“The on court temperature I was told was 41 degrees on court when I was playing, so it was very hot,” he added. “That changes the way the court plays and the way the match plays out, too.

"So I was glad to get off in three sets, in a couple of hours, because ideally you don't want to be playing extremely long matches in those conditions because it's tough.

“For me it's a bit frustrating because you obviously want to go out there and sort of perform as best you can, whereas today I didn't feel like I was able to do that because of the way that he was playing.

"He was hitting the ball this high over the net and so flat and down the line. It's very difficult to dictate points when your opponent's playing like that.

"I could have obviously finished the second set a little bit better and served well at that period. But apart from that sort of 15, 20 minute period, I was quite comfortable the rest of the match.”

Brandishing a set of stats from the match, he said: “It doesn't say on this match report how well I played, it just says that I won the match,” he said. “That's the most important thing.”

The Scot has previously suffered from mouth ulcers in the run up to Wimbledon, but the tingling sensation is absent this year. The world No.3 is coming off the best start to a season in his career and is a calm, mature presence as he attempts to reclaim the title which he won back in 2013.

“I have no ulcers this year,” he said. “I felt pretty good coming in. I practised well. And I felt fairly calm. It wasn't too hectic.

"When I spoke to my team about the match, I expected it to be difficult, and prepared for that. I didn't feel unbelievably nervous. But there were still goosebumps and stuff, butterflies in the stomach when you walk out there.”

He is joined in the fourth round of the men’s draw at Wimbledon by three other Brits for the first time since 2006. After Liam Broady on Monday, yesterday it was the turn of James Ward and Aljaz Bedene.

Ward came through 6-7 (4), 6-2, 6-4, 6-3 against Italian wild card Luca Vanni, while Bedene, a naturalised Slovenian, was a 7-5, 1-6, 4-6, 6-3, 6-4 winner against Czech veteran Radek Stepanek.

While he enjoys encouraging the next generation of British talent, Murray said it wasn’t his job to capitalise on his own successes.

“That's the job of the LTA, to capitalise on any success that players have just now,” he said. “That isn't up to me, I don't think.

"But what I do enjoy doing is being around the other British players, chatting to them, helping them, practicing with them. You know, being around them is good for me, as well. It helps them, too. So it's win win really.”

Murray, who drives into training from his home in Oxshott, Surrey, each day said that he had been diverted by media coverage of the atrocity in Tunisia, where 38 people were killed by a gunman.

“Because I drive in each day, I've listened to a lot of sort of phone ins and stuff on the radio, people that have been affected by it,” he said.

“It's absolutely horrific. But I don't know exactly what role athletes play in times like this and how exactly we can help.”